Frankfurt or Interlaken?

Neither city is a beach destination, but Interlaken at least has swimmable water close by. Frankfurt has no sea anywhere near, so locals cool off in outdoor pools and gravel-pit lakes such as the Langener Waldsee in the southern forest. The Main is for sitting beside, not swimming in.

In Interlaken, Lake Thun warms up enough in high summer for the lidos and small shingle beaches at Neuhaus and towards Spiez, with snow peaks behind. Turquoise Lake Brienz is colder. It makes a good swim after a hike, but only for a few weeks of the year.

Frankfurt has real local food culture, which Interlaken lacks. Long shared tables in the Sachsenhausen apple-wine taverns, Grüne Soße and Handkäs mit Musik, and the stalls of the Kleinmarkthalle give a trip some regional flavour. The Bahnhofsviertel's cheap global kitchens add range.

Interlaken's restaurants mostly serve fondue, rösti and international dishes to visitors. The food is reliable but forgettable. Its better meals happen higher up: cheese from a mountain dairy or lunch on a hut terrace above Grindelwald.

Here the gap is wide. Frankfurt has the Museumsufer, where the Städel's old masters sit alongside museums of film, architecture and Jewish history. It also has the rebuilt Römer and old-town lanes, the Paulskirche and Goethe's birthplace, all within a short walk, under Germany's only real skyline.

Interlaken offers a row of grand hotels on the Höheweg, a few old timber houses across the Aare in Unterseen and a small local museum. Anyone who wants museums or historic streets will need to take the train to Bern or Thun.

Frankfurt has far more going on after dark, though mostly at weekends. Its techno and house tradition, shared with Offenbach, lives on in a small club scene. The Bahnhofsviertel has cocktail bars and late kiosks, and Berger Straße has relaxed neighbourhood bars.

Interlaken goes to bed early because its visitors are catching dawn trains. A few backpacker pubs, basement clubs near the hostels and the Kursaal casino are about all there is, and the streets are quiet before midnight.

This is where Interlaken is in a different league. The Eiger, Mönch and Jungfrau, the waterfalls of the Lauterbrunnen valley and the Aletsch glacier seen from the Jungfraujoch are all within an hour. Paragliding, canyoning, rafting on the Lütschine and winter skiing around Wengen and Mürren start from town. The one risk is low cloud hiding the peaks.

Frankfurt's outdoors is green and gentle. The Taunus beech woods and the Großer Feldberg are a short ride away, and the city has the Stadtwald and long, flat cycle paths along the Main. It suits walkers and cyclists, not anyone looking for drama.

Both are good bases, but Frankfurt reaches more places, and more varied ones. High-speed trains bring Cologne cathedral and Würzburg's Residenz into easy range, and Heidelberg and the castle-lined Rhine Gorge are about an hour away. Closer still are Mainz with its Gutenberg Museum, the spa town of Wiesbaden and Darmstadt's Art Nouveau colony.

Interlaken's trips are smaller in scale but very attractive. You have Bern's arcaded old town, Thun's castle, steamer stops at Spiez and Oberhofen, the Ballenberg open-air museum and the line over the Brünig Pass to Lucerne.

Interlaken makes the more memorable family trip, because getting around is half the fun. Rack railways, gondolas and steamers, summer toboggan runs and cliff walks at the summit stations, the St Beatus caves and the animals at Ballenberg all go down well. Wet days and high altitudes are the weak points.

Frankfurt covers exactly those weak points. The Senckenberg's dinosaur hall, the central zoo and the Palmengarten glasshouses fill a rainy day, and trams take pushchairs easily. There is just less to excite children.

Both are easy without a car, in different ways. Frankfurt has a full urban network of U-Bahn, S-Bahn and trams, which takes some learning across its zones, with the airport about a quarter of an hour from the centre and high-speed trains from the main station.

Interlaken is a small, flat town you can walk end to end. What matters is the mountain network beyond it: narrow-gauge lines, cog railways, gondolas and lake steamers that connect neatly, though they get crowded in summer.

Frankfurt is a proper shopping city. It has department stores and malls on the Zeil, luxury houses around Goethestraße, and independent boutiques and delis on Berger Straße and Schweizer Straße.

Interlaken's Höheweg sells watches, army knives, cuckoo clocks and chocolate to tour groups, plus outdoor gear. The one craft worth buying is woodcarving from Brienz.

Neither is cheap, but Frankfurt is much easier on the wallet. Hotels are the expensive part, and they become scarce during trade fairs. Weekends and summer bring rates down, and eating in taverns and Turkish grills costs little.

Interlaken charges full Swiss prices for everything. On top of that come the mountain railways and cable cars, the Jungfraujoch above all, and adventure sports. Hostels, picnics and transport passes help, but there is no budget way to see the region properly.

Frankfurt has a full cultural season. Its opera company is known for adventurous productions, the Alte Oper hosts the radio symphony orchestra, and there is serious drama at the Schauspiel, dance at the Mousonturm and jazz in old cellar clubs. Most of it runs from autumn to early summer.

Interlaken's live performance mostly happens in summer: the amateur open-air William Tell in the woods, yodelling and alphorn evenings, and a lake-stage musical in Thun. For anything more, you go to Bern.

Frankfurt itself is not restful, but it puts you near real spa towns. Wiesbaden's Art Nouveau Kaiser-Friedrich-Therme and the thermal baths of Bad Homburg are both easy trips, and in town the Palmengarten is the calmest place.

Interlaken has no springs of its own. Rest there means hotel spas on the Höheweg, early mornings by the lake and slow steamer crossings. The busy centre is not restful, so people who want quiet stay up in Wengen or Mürren.